The challenge went unpunished, which has upset United, because Fellaini is now out of tomorrow’s game and may also miss United’s Premier League clash against Crystal Palace on Saturday.

Fellaini will undergo further medical tests this week to determine the extent of the damage, amid fears he could be sidelined for several games.

Manchester United players on the plane to Russia (Image: Manchester United)

Chris Smalling, Jesse Lingard and Marcus Rashford at Manchester Airport on their way to Moscow (Image: Manchester United)

With Paul Pogba out with a hamstring injury, Fellaini had emerged as Mourinho’s go-to man in central midfield, with the United boss having placed his faith and trust in the Belgium international.

Fellaini’s enforced loss has opened the door to United skipper Michael Carrick, who has been a peripheral figure so far this season, and Ander Herrera, who has also been pushed out of the picture by the arrival of Nemanja Matic from Chelsea.